Sn modified carbon support PdCo bimetallic oxide for boosting low-temperature dehydrogenation of dodecahydro-N-ethylcarbazole

Abstract

Liquid organic hydrogen carriers (LOHCs) have garnered considerable attention and have undergone extensive studies owing to their high hydrogen storage density and ease of storage and transportation. Research has shown that carbon-supported bimetallic alloys exhibit exceptional performance as catalysts for low-temperature dehydrogenation. Nevertheless, developing high-efficiency carbon support catalysts and revealing the interaction between active metals and support remains challenging but significant. In this work, a cost-effective metal-modified activated carbon (AC) was synthesized and loaded with PdCoO active sites for low-temperature dehydrogenation of dodecahydro-N-ethylcarbazole (12H-NECZ) to produce hydrogen. The results show that: (1) Introducing tin (Sn) into the AC support to form highly dispersed PdCoO/Sn₂-C improves the pore distribution and size of the catalyst, promoting the dispersion of active metals on the surface; (2) The interface effect between PdCoOx and Sn-C supports effectively regulates the electron transfer inside the catalyst, enhances the synergistic effect between metals, and reduces electron transfer resistance, thereby improving dehydrogenation catalytic activity. The results show that at 140 °C, 12H-NECZ was completely dehydrogenated after 8 h, with a selectivity of 92.5%, while the palladium loading was only 2.2 wt%. This study provides a suitable method for the targeted design of catalysts by altering the electronic effects of supports.